KR20190003284A - Method of stiction prevention by patterned anti-stiction layer - Google Patents

Abstract

The present invention relates to a MEMS device having a patterned anti-adhesion layer and a related forming method. The MEMS device has a handle substrate defining a first bonding surface, and a MEMS substrate having the MEMS device defining a second bonding surface. The handle substrate is bonded to the MEMS substrate through a bonding interface with the first bonding surface facing the second bonding surface. The anti-adhesion layer does not sit on the bonding interface but is arranged between the first bonding surface and the second bonding surface.

Description

METHOD OF STICKING PREVENTION BY PATTERNED ANTI-STICTION LAYER [0002]

This application claims priority from U.S. Provisional Application No. 62 / 527,225, filed June 30, 2017, the contents of which are incorporated herein by reference in their entirety.

Microelectromechanical systems (MEMS) devices, such as accelerometers, pressure sensors and gyroscopes, have shown widespread use in many of today's electronic devices. For example, MEMS accelerometers are typically installed in automobiles (e.g., airbag deployment systems), tablet computers, or smart phones. For many applications, a MEMS device is electrically connected to an application-specific integrated circuit (ASIC) to form a complete MEMS system.

Embodiments of the disclosure are best understood from the following detailed description when read in conjunction with the accompanying drawings. Note that according to standard practice in the industry, various features are not shown to scale. Indeed, the dimensions of the various features may be arbitrarily increased or decreased for clarity of discussion.
1A illustrates a cross-sectional view of some embodiments of a MEMS device handle substrate.
Figure IB illustrates a cross-sectional view of some embodiments of a MEMS device handle substrate having a MEMS substrate formed thereon.
Figure 1C illustrates a cross-sectional view of some embodiments of a MEMS device handle substrate having a patterned MEMS substrate formed thereon.
Figure ID illustrates a top view of some embodiments of MEMS devices.
Figure IE illustrates a cross-sectional view of some embodiments of the MEMS device being energized.
2A illustrates a cross-sectional view of some embodiments of a MEMS device in which an anti-adhesion layer is formed on an entire handle substrate.
FIG. 2B illustrates a cross-sectional view of some embodiments of the MEMS device of FIG. 2A with force being applied.
Figures 3A-3C illustrate cross-sectional views of various embodiments of patterning of the anti-adhesion layer in a MEMS device.
Figures 4 to 6 illustrate cross-sectional views of some embodiments of the enlarged portion of the MEMS device of Figures 3A-3C.
Figure 7 illustrates a cross-sectional view of several alternative embodiments of a MEMS device having a roughened and patterned antiadhesive layer.
Figures 8 and 9 illustrate cross-sectional views of some embodiments of an enlarged portion of a MEMS device having a conductive metal layer.
10 and 11 illustrate cross-sectional views of several alternative embodiments of a MEMS device having a patterned anti-adhesion layer.
Figures 12 and 13 illustrate cross-sectional views of some embodiments of a method for manufacturing a MEMS device having a patterned anti-adhesion layer.
14 illustrates a flow diagram of some embodiments of a method for manufacturing a MEMS device having a patterned anti-adhesion layer.

The present disclosure provides many different embodiments, or examples, for implementing the different features of the present disclosure. Specific examples of components and arrangements for simplifying this disclosure are described below. Of course, this is for illustrative purposes only and is not intended to be limiting. For example, in the ensuing description, the formation of the first feature on the second feature or on the second feature may include an embodiment in which the first feature and the second feature are formed in direct contact, and the first feature and / An additional feature may be formed between the first feature and the second feature such that the second feature may not be in direct contact. Furthermore, the present disclosure may repeat the reference numerals and / or characters in various instances. Such repetition is for the purpose of simplicity and clarity and does not in itself affect the relationship between the various embodiments and / or configurations discussed.

Also, spatial relative terms, such as "under", "under", "below", "above", "above", etc., refer to one or more of the other element (s) May be used herein for ease of explanation to illustrate the relationship of the elements or features of the device. Spatial relative terms are intended to encompass different orientations of the device being used or operating, in addition to the orientation shown in the figures. The device may be otherwise oriented (rotated at 90 [deg.] Or other orientation) and the spatial relative descriptor used herein may be interpreted accordingly.

Some microelectronic system (MEMS) devices, such as accelerometers and gyroscopes, include a movable mass, and neighboring fixed electrode plates arranged in the cavity. The movable mass is movable or flexible to a fixed electrode plate that is responsive to external stimuli such as acceleration, pressure, or gravity. A change in distance between the movable mass and the fixed electrode plate through the capacitive coupling of the movable mass and the fixed electrode plate is detected and transferred to the measurement circuit for further processing.

During the bulk manufacturing of a MEMS device according to some methods, a handle substrate (also referred to as a handle wafer) is formed, the handle substrate comprising a complementary metal-oxide-semiconductor (MR) wafer having support logic for the associated MEMS device. CMOS) wafer and bonded to this complementary metal oxide semiconductor (CMOS) wafer. According to one example, a MEMS substrate may be bonded to a handle substrate, and a eutectic bonding substructure may be formed on the surface of the MEMS substrate. According to one exemplary aspect, a MEMS device is also formed within the MEMS substrate, e.g., by a variety of patterning methods. In addition, the cap substrate may be bonded to the MEMS substrate using a eutectic bonding substructure for eutectic bonding. When the cap substrate is bonded to the MEMS substrate, the substrate is unified with a die each including at least one MEMS device, and packaging is completed.

According to one example, FIG. 1A illustrates an exemplary handle substrate 100, wherein the handle substrate 100 includes a base substrate 102 having a routing metal layer 104 formed thereon and patterned. The routing metal layer 104 may comprise, for example, aluminum, a metal such as copper, or other metals. An oxide layer 106 is also formed and patterned over the routing metal layer 104, and a bump feature 108 is also formed over the routing metal layer. The bump feature 180 may be comprised of, for example, an oxide, a metal, or other material.

When the handle substrate 100 is formed, the MEMS substrate 110 is bonded to the handle substrate 100 by, for example, fusion bonding as illustrated in FIG. 1B. The MEMS substrate 110 is also patterned to define a movable mass 112 of the MEMS device 114, for example, as illustrated in Figure 1C, and a layer of bonding material 116 is formed over the MEMS substrate 110 Or alternatively patterned, and the bonding material layer 116 may be comprised of a metal such as germanium, aluminum, gold, or other conductive material. It is also noted that the bonding material layer 116 may be a metal for eutectic bonding and the bonding material layer 116 may alternatively comprise a non-conductive material configured to act as a bonding material. For example, the layer of bonding material 116 may comprise one or more of a polymer to provide adhesive bonding and an oxide to provide a fusion bonding. 1D illustrates a top view 118 of a MEMS device 114 and FIG. 1C illustrates a cross-section 120 of a MEMS device 114. For clarity purposes, FIG. For example, approaches have been used to perform surface treatments to alter the hydrophilic properties of surfaces or to coat movable masses or cavity surfaces to attempt to limit surface adhesion. However, this approach is difficult to integrate with various manufacturing processes and introduces contamination.

Due to the movable or flexible portion, MEMS devices have some production challenges that are not encountered in conventional CMOS circuits. One significant challenge for MEMS devices is surface adhesion. Surface adhesion refers to the tendency of a flexible or flexible MEMS portion to contact a neighboring surface and " stick " to a neighboring surface. This " sticking " may occur at the end of manufacture such that the movable or flexible portion is not sufficiently released from the neighboring surface, or occurs when the component suddenly " sticks "

For example, by moving [as indicated by arrow 112] of the movable mass 112 of the MEMS device 114 (e.g., due to acceleration, gravity, pressure, etc.) in Figure IE, Can contact the features 108, and surface adhesion can hinder the ability of the movable mass to return to its original position. As feature size shrinks for next-generation technologies, surface sticking is becoming an increasingly important consideration in MEMS devices. Surface adhesion may occur due to any one of several different effects, such as capillary forces, van der Waals forces of molecules or electrostatic forces between neighboring surfaces. The extent to which this effect causes adhesion may vary based on many different factors such as the temperature of the surface, the contact area between the surfaces, the contact potential difference between the surfaces, whether the surface is hydrophilic or hydrophobic, and so on.

One way to prevent such adhesion between the movable mass 112 and the bump feature 108 is to form the anti-adhesion layer 124 on the handle substrate 100 as illustrated in FIG. 2A. The antiadhesive layer 124 suppresses adhesion between the movable mass 112 and the bump feature 108 upon contact of the bump feature 108 and the movable mass 112, as illustrated, for example, in FIG. 2B , Allowing the movable mass 112 to return to its original position 126 in Figure 2a without sticking. Typically, however, such an anti-adhesion layer 124 coats the exposed surfaces and all features, such as the routing metal layer 104, the oxide layer 106, as well as the bump features 108. However, the challenge in fabricating a MEMS device according to the previous method relates to the bonding of the MEMS substrate 110 to its associated handle substrate 100. When the anti-adhesion layer is applied, all surfaces of the MEMS substrate 110 or the handle substrate 100 are coated with the anti-adhesion layer 124. However, such an anti-adhesion layer 124 reduces the reliability of the bond (e. G., Fusion bond or eutectic bond) in the bonding region 128, potentially resulting in failure of substrate bonding.

The present application relates to a MEMS device having a patterned antiadhesive layer to improve adhesion properties and bonding, and an associated method of forming such a MEMS device. The MEMS device of the present disclosure includes a MEMS substrate that is bonded to a handle substrate. An anti-stick layer is disposed on at least one of the MEMS substrate and the handle substrate, and the anti-stick layer comprises a pattern such that there is no anti-adhesive layer in one or more areas associated with the interface between the MEMS substrate and the handle substrate. The anti-adhesion layer is patterned, for example, on at least one of a handle substrate and a MEMS substrate. Thus, adhesion can be avoided at the end of the manufacturing process and / or during normal operation of the MEMS device, and suitable bonding between the MEMS substrate and the handle substrate is achieved where desired, thereby improving reliability. Although the concepts relating to some exemplary MEMS devices will be exemplified herein, it will be appreciated that this concept may be applied to appropriate MEMS devices utilizing movable parts, including, for example, actuators, valves, switches, microphones, pressure sensors, accelerometers, and / or gyroscopes. Will be understood to be applicable.

Figures 3A-3C illustrate a series of cross-sectional views of some embodiments of a method for manufacturing a MEMS device having a patterned anti-adhesion layer at various stages of manufacture.

In accordance with some exemplary aspects of the present disclosure, FIG. 3A illustrates an exemplary handle substrate 200. According to some embodiments, the handle substrate 200 includes a base substrate 202 having a routing metal layer 204 formed thereon and patterned. The routing metal layer 204 may comprise, for example, aluminum, a metal such as copper, or other metals. An oxide layer 206 is also formed and patterned over the routing metal layer 204 and a bump feature 208 is also formed over the routing metal layer 204. The bump feature 208 protrudes outward from the top surface of the routing metal layer 204. The bump feature 280 may be comprised of, for example, an oxide, a metal, or other material.

An anti-adhesion layer 210 is formed on the substrate 212 (shown in FIG. 3A) of the handle substrate 200, as illustrated in the example shown in FIG. 3B. In some embodiments, the anti-adhesion layer 210 of FIG. 3B includes, for example, an organic material formed over the surface 212. In some embodiments, the formation of the anti-adhesion layer 210 can be accomplished in various ways, for example by deposition of a polymer film, or a single layer, by dipping, spin coating, sputtering, and chemical vapor deposition Can be achieved by depositing an organic material.

3C, the anti-adhesion layer 210 is patterned and the anti-adhesion layer 210 associated with one or more predetermined locations 214 of the handle substrate 200 is removed, so that at least one adhesion location 216 But does not cover one or more predetermined locations 214 while maintaining the anti-adhesion layer 210. The one or more predetermined locations 214 at least include a bonding region 218 associated with bonding of the handle substrate 200 to the MEMS substrate 234, for example, as discussed below.

In one example, the one or more tacky locations 216 are associated with the bump features 208. For example, in one embodiment, the anti-adhesion layer 210 may be arranged along the sidewalls and top surface on the top surface of the routing metal layer 204 and also on opposite sides of the bump feature 208. In such an embodiment, the anti-adhesion layer 210 has a bottom surface that is aligned with the bottom surface of the bump feature 208 along a horizontal plane. In another embodiment, the anti-adhesion layer 210 may be arranged on the top surface of the routing metal layer 204 and also along one sidewall of the bump feature 208, but not along the opposite sidewall of the other. In yet another embodiment, the anti-adhesion layer 210 may be arranged on the top surface of the routing metal layer 204 and without following the sidewalls of the bump feature 208. In another example of this disclosure, the anti-adhesion layer 210 is physically etched or abraded at one or more predetermined locations 214. In another example, the anti-adhesion layer 210 is chemically etched at one or more predetermined locations 214.

According to one embodiment of the present disclosure, the anti-adhesion layer 210 is patterned by a photolithographic process. In another embodiment, the anti-adhesion layer 210 is patterned by physical or chemical etching using various other techniques through various semiconductor processing techniques such as dry plasma etching, wet-tank etching, or other etching techniques. In some embodiments in which the anti-adhesion layer 210 is patterned by a photolithographic process, the outermost sidewalls of the anti-adhesion layer 210 have sloped sidewalls. For example, the outermost sidewall of the anti-adhesion layer 210 may have a sidewall oriented at an angle greater than 0 degrees with respect to a normal that extends vertically outward from the top surface of the routing metal layer 204. [

As illustrated in the example illustrated in Figure 4, the one or more tacking locations 216 may include a surface 224 of the feature 224 of the handle substrate 200, such as the bump feature 208 shown in Figure 3C, MEMS-facing surface (s) 220 and one or more sidewalls 222. One or more adhesion locations 216 may be associated with the MEMS-facing surface 220 and one sidewall 222 of the features 224 of the handle substrate 200, as illustrated in the example illustrated in Figure 5 . Similarly, as illustrated in the example shown in FIG. 6, the one or more tacking locations 216 may be associated with the surface 220 of the features 224 of the handle substrate 200 facing the MEMS. While one or more tacking locations 216 are shown and discussed herein in connection with one or more of the surfaces 220 and sidewalls 222 of the features 224 of the handle substrate 200 that face the MEMS, 216 may be associated with any surface of any feature 224 described herein.

In another embodiment of the present disclosure, as illustrated in the example shown in FIG. 7, the anti-adhesion layer 210 may also be rubbed at one or more of the adhesion locations 216. For example, the surface 226 of the anti-adhesion layer 210 is physically or chemically rubbed by treating the surface with, for example, a physical abrasion with a predetermined roughness or with a plasma provided therein. Roughing or otherwise altering the surface 226 of the anti-adhesion layer 210, for example, also generally suppresses adhesion as described above. Alternatively, the surface 220 of the feature 224 facing the MEMS may be first rubbed, and the anti-adhesion layer 210 may also be deposited on the surface 220 of the feature 224 facing the MEMS.

Note that the present disclosure may be implemented by patterning the anti-adhesion layer 210, by lubrication of the anti-adhesion layer 210, or by patterning and rubbing the anti-adhesion layer 210. Alternatively, any surface can be rubbed before the anti-adhesion layer 210 is formed thereon and patterned. As such, the combination of providing the anti-adhesion layer 210 patterned or roughened to the one or more adhesion locations 216 is considered to be within the scope of this disclosure.

8 illustrates one of more than one tacking position 216 and illustrates the surface 220 of the feature 224 of the handle substrate 200 facing the MEMS and the one or more sidewalls 220. In accordance with another exemplary embodiment of the present disclosure, (222) is covered by the anti-adhesion layer (210). However, as shown in FIG. 8, a conductive layer 228 is also provided between the feature 224 (e.g., the bump feature 208 shown in FIG. 3C) and the anti-adhesion layer 210. In this embodiment, the conductive layer 228 may comprise a low resistivity material. For example, the conductive layer 228 may comprise a thin layer of silicon, polysilicon, aluminum, copper, titanium, titanium nitride, or any suitable electrically conductive material. The conductive layer 228 is configured to release and / or disperse any charge accumulation upon or near the MEMS feature in the feature 224, as discussed above, for example. One or more tacking locations 216 are associated with the surface 220 and sidewalls 222 of the features 224 of the handle substrate 200 that face the MEMS, 228 include a thin conductive layer disposed between the features 224 and the anti-adhesion layer 210.

9 illustrates another example of one or more tacking locations 216 and illustrates a surface 220 of the features 224 of the handle substrate 200 facing the MEMS and one or more sidewalls 222, Is covered by the anti-adhesion layer (210). 9, a conductive layer 228 as described above is also provided between the feature 224 (e.g., the bump feature 208 shown in FIG. 3C) and the anti-adhesion layer 210. FIG. 8, in which the conductive layer 228 has a portion 230 not covered by the anti-adhesion layer 210, in the example shown in FIG. 9, the conductive layer 228 is formed of an anti- 210). ≪ / RTI > Figure 9 also illustrates an example in which a via or via array 231 may be provided in the feature 224 that is also sealed by the anti-adhesion layer 210. The conductive layer 228 can be formed by any suitable process such as, for example, low pressure chemical vapor deposition (LPCVD), plasma enhanced chemical vapor deposition (PECVD), or atmospheric pressure chemical vapor deposition (APCVD) growth process. ≪ / RTI > In some embodiments, the conductive layer 228 may comprise aluminum (Al), nickel (Ni), or copper (Cu).

According to another exemplary embodiment shown in FIG. 10, an anti-adhesion layer 210 may be provided directly on the routing metal layer 204. In another example, an anti-adhesion layer 210 may be provided on the oxide layer 206. Similarly, an anti-adhesion layer 210 may be provided on any surface of the handle substrate 200, for example, immediately above the silicon substrate 232, as illustrated in the example shown in FIG.

According to another exemplary embodiment of the present disclosure, FIG. 12 shows a MEMS substrate 234, by fusion bonding of the MEMS substrate 234 to the handle substrate 200, e.g., in one or more bonding regions 218, RTI ID = 0.0 > 200 < / RTI >

For example, the handle substrate 200 of FIG. 10 defines a first bonding surface 236 and the MEMS substrate 234 of FIG. 12 defines a second bonding surface 238. The handle substrate 200 is bonded to the MEMS substrate 234 at the bonding interface 240 with the first bonding surface 236 facing the second bonding surface 238. [ The bonding interface 240 is associated with, for example, the bonding area 218 of the handle substrate 200. Thus, the anti-adhesion layer 210 is arranged between the first bonding surface 236 and the second bonding surface 238, but does not reside above the bonding interface 240.

The MEMS substrate 234 may comprise a semiconductor material. For example, in some embodiments, the MEMS substrate 234 may comprise a silicon material, such as doped polysilicon. In various embodiments, the MEMS substrate 234 may include one or more MEMS devices each having a movable mass arranged in close proximity to the bump feature 208. For example, in some embodiments, the MEMS substrate 234 may include an accelerometer, gyroscope, digital compass, and / or pressure sensor.

In some embodiments, the handle substrate 200 may include active and / or passive semiconductor devices configured to support the functioning of a MEMS device within the MEMS substrate 234. In some embodiments, For example, the handle substrate 200 may include a transistor device (e.g., a MOSFET device) configured to provide signal processing of data collected from a MEMS device in a MEMS substrate 234. [ In some embodiments (not shown), a back-end-of-the-line (BEOL) metal interconnect stack may be disposed on the opposite side of the handle substrate 200 from the MEMS substrate 234. The BEOL metal stack includes a plurality of conductive interconnect layers (e.g., copper and / or aluminum layers) arranged in a dielectric structure arranged along the handle substrate 200. The plurality of metal interconnect layers are coupled to the one or more transistor devices. Generally, the plurality of metal interconnect layers increase in size as the distance from the semiconductor substrate increases, such that one or more transistor devices are connected to off-chip elements.

In some embodiments, a capping substrate (not shown) may be arranged on the opposite side of the MEMS substrate 234 from the handle substrate 200. The capping substrate includes a recess that is disposed within the surface of the capping substrate facing the MEMS substrate 234. [ A capping substrate is bonded to the MEMS substrate to form a hermetically sealed cavity extending between the recess and the handle substrate 200. The hermetically sealed cavity includes a MEMS device in MEMS substrate 234 and a bump feature 208 and an anti-adhesion layer 210. In some embodiments, the cavity may be maintained at a predetermined pressure selected based on the MEMS device in the cavity. For example, the pressure in the cavity surrounding the accelerometer may be different from the pressure in the cavity surrounding the gyroscope.

In some embodiments, the capping substrate may comprise a semiconductor material. For example, the capping substrate may comprise a silicon substrate. In some embodiments, the capping substrate can be connected to the MEMS substrate 234 by a eutectic bond that includes one or more metallic materials.

An anti-adhesion layer 210 may be patterned on a handle-facing surface 242 of the MEMS substrate 234, as illustrated in another exemplary embodiment shown in FIG. 13, There is shown another exemplary MEMS device 237 in which the anti-adhesion layer 210 does not cover one or more of the adhesion locations 216 associated with the anti- Patterning of the anti-adhesion layer 210 on the MEMS substrate 234 may be performed as discussed above. It is also noted that a conductive material such as aluminum, titanium, or other conductive material may reside below the anti-adhesion layer 210 being patterned thereon. In some such embodiments, the anti-adhesion layer 210 may not be arranged along the various surfaces of the handle substrate 200 (e.g., along the bump feature 208). In another embodiment, the anti-adhesion layer 210 may be additionally arranged along the surface of the handle substrate 200.

For example, the MEMS substrate 234 is patterned to form a MEMS device 244 that includes the movable mass 246. A MEMS device may be, for example, a microvalve, microswitch, microphone, pressure sensor, accelerator, gyroscope or any other device having a movable or flexible portion that is moved or flexed relative to a fixed portion A microactuator or a microsensor.

14 illustrates a flow diagram of some embodiments of a method 300 for manufacturing a MEMS device having a patterned anti-adhesion layer, according to the present disclosure.

Although the disclosed method 300 is illustrated and described herein as a sequence of operations or events, it should be understood that the illustrated sequence of events or events should not be construed in a limiting sense. For example, some operations may occur in different orders and / or concurrently with other operations or events, as illustrated and / or described herein. Furthermore, to implement one or more aspects or embodiments of the present disclosure, not all illustrated acts may be required. Further, one or more of the operations illustrated herein may be performed in one or more separate operations and / or steps.

In operation 302, an anti-adhesion layer is formed on or otherwise provided on each of the one or more surfaces of the handle substrate and the MEMS substrate. Providing an anti-adhesion layer in operation 302 may include depositing an organic material on one or more respective surfaces of the handle substrate and the MEMS substrate.

In some embodiments, the handle substrate may have any type of semiconductor and / or epitaxial layer formed thereon and / or otherwise associated therewith, as well as a semiconductor wafer on the wafer or any type of semiconductor (E. G., Silicon / CMOS bulk, SiGe, SOI, etc.). In some embodiments, prior to forming the anti-adhesion layer, one or more active devices may be formed within the handle structure. For example, one or more transistor devices may be formed in a handle substrate using a complementary metal oxide semiconductor (CMOS) process. In various embodiments, the organic material may be deposited by physical vapor deposition techniques (e.g., PVD, CVD, PE-CVD, ALD, etc.). In another embodiment, the organic material may be deposited by a spin coating technique.

In operation 304, the anti-adhesion layer is patterned. In operation 304, the patterning of the anti-adhesion layer generally defines a patterned anti-adhesion layer that does not cover one or more predetermined locations associated with bonding of the handle substrate to the MEMS substrate. Patterning the anti-adhesion layer may include, for example, physically removing the organic material from one or more predetermined locations. Alternatively, patterning the antiadhesive layer may comprise rubbing the substrate on which the organic material or organic material thereon is formed, in one or more predetermined locations.

In another alternative example, patterning the anti-adhesion layer comprises rubbing the surface of each handle substrate and MEMS substrate associated with one or more predetermined locations. For example, patterning the antiadhesive layer can include plasma etching the surface of each handle substrate and MEMS substrate associated with one or more predetermined locations. In some embodiments, the plasma etch may have an etch chemistry that includes a fluorine species (e.g., CF4, CHF3, C4F8, etc.).

In yet another alternative, patterning the antiadhesive layer may comprise performing a photolithographic process on the MEMS substrate and / or the handle substrate. In such an embodiment, a photosensitive layer is formed on the anti-adhesion layer 210. In various embodiments, the photosensitive layer may comprise a photoresist layer (e.g., a positive or negative photoresist) formed on the anti-adhesion layer by a spin coating process. The photosensitive material is then exposed to electromagnetic radiation (e.g., ultraviolet light, extreme ultraviolet light, etc.) along with the photomask. Electromagnetic radiation alters the solubility of the exposed areas in the photosensitive material to define the soluble areas. The photosensitive material is then developed to define a patterned layer of photosensitive material having an opening formed by removing the soluble region. The anti-adhesion layer is then etched along the patterned layer of photosensitive material. In various embodiments, the anti-adhesion layer may be selectively exposed to the etchant in areas not covered by the patterned layer of photosensitive material (e.g., a photoresist layer and / or a hardmask layer). In some embodiments, the etchant may comprise a dry etchant having an etch chemistry that includes a fluorine species (e.g., CF4, CHF3, C4F8, etc.). In another embodiment, the etchant may comprise a wet etchant comprising hydrofluoric acid (HF) or potassium hydroxide (KOH).

In another example, patterning the antiadhesive layer at operation 304 may include one or more of a physical etch and a chemical etch at one or more predetermined locations. In some examples, the anti-adhesion layer remains on the at least one feature associated with the MEMS device after patterning.

In operation 306, the handle substrate is bonded to the MEMS substrate at one or more predetermined locations. In various embodiments, the MEMS substrate may include one or more MEMS devices each comprising a movable mass. For example, in some embodiments, the MEMS substrate may include an accelerometer, gyroscope, digital compass, or pressure sensor. The handle substrate may be bonded to the MEMS substrate such that the movable mass is arranged at a position just above the patterned anti-adhesion layer. This allows the anti-adhesion layer to reduce adhesion of the movable mass during operation of the MEMS device.

In one example of this disclosure, bonding a handle substrate to a MEMS substrate at one or more predetermined locations comprises fusion bonding the handle substrate to the MEMS substrate at one or more predetermined locations. In another embodiment, a bonding structure comprising one or more adhesive materials may be used to bond the handle substrate to the MEMS substrate.

In some alternatives to this disclosure, a conductive layer may be formed on at least one of the handle substrate and the MEMS substrate prior to forming the anti-adhesion layer in operation 304, and the conductive layer may be applied to the handle substrate and the MEMS substrate . Forming the conductive layer may further include patterning the conductive layer in, for example, at least one region associated with the at least one adhesive location, wherein the conductive layer is in contact with the metal layer.

Thus, as can be appreciated from the above, the present disclosure relates to MEMS devices having patterned antiadhesive layers for enhancing adhesion properties, and related methods of forming such MEMS devices.

In one embodiment, the MEMS device includes a handle substrate defining a first bonding surface. The MEMS substrate having the MEMS device defines the second bonding surface, and the handle substrate is bonded to the MEMS substrate through the bonding interface with the first bonding surface facing the second bonding surface. The anti-adhesion layer is also not disposed on the bonding interface and is also arranged between the first bonding surface and the second bonding surface.

In another embodiment, a method for manufacturing a MEMS device is disclosed, wherein an anti-adhesion layer is formed on at least one surface of a handle substrate and a MEMS substrate. The anti-adhesion layer is patterned to define a patterned anti-adhesion layer that does not cover one or more predetermined locations associated with bonding of the handle substrate to the MEMS substrate. In addition, the handle substrate is bonded to the MEMS substrate at one or more predetermined locations.

The foregoing is a summary of features of some embodiments to enable those skilled in the art to more fully understand aspects of the disclosure. Those skilled in the art will recognize that they can readily use the present disclosure as a basis for designing or modifying other processes and structures to implement the same objectives and / or to achieve the same advantages as the embodiments disclosed herein . Those skilled in the art should also be aware that such equivalent constructions do not depart from the spirit and scope of this disclosure and that various changes, substitutions, and alterations can be made herein without departing from the spirit and scope of this disclosure.

Examples

Example 1. In microelectromechanical systems (MEMS) devices,

A handle substrate defining a first bonding surface;

A MEMS substrate having a MEMS device and defining a second bonding surface, wherein the handle substrate is bonded to the MEMS substrate via a bonding interface with the first bonding surface facing the second bonding surface. ; And

And an anti-stiction layer disposed between the first bonding surface and the second bonding surface without residing on the bonding interface.

Example 2. The handle substrate of embodiment 1, wherein the handle substrate comprises a handle feature associated with the MEMS device, wherein the anti-adhesion layer is arranged on at least one of a MEMS-facing surface of the handle feature and a sidewall MEMS device.

Example 3. The MEMS device of embodiment 1 wherein the MEMS device comprises a MEMS feature and wherein the anti-adhesion layer is arranged on at least one of a handle-facing surface and one or more sidewalls of the MEMS feature. .

Example 4. The MEMS device of embodiment 1, wherein the anti-adhesion layer is arranged on both the handle substrate and the MEMS substrate.

Example 5. The MEMS device of embodiment 1, wherein the at least one predetermined location comprises at least one bonding location, and wherein the handle substrate and the MEMS substrate are fusion bonded to each other at the one or more bonding locations.

Example 6. A conductive layer is also disposed between the anti-adhesion layer and each of the handle substrate and the MEMS substrate in Example 1, and the conductive layer generally releases electrical charge associated with each of the handle substrate and the MEMS substrate And the MEMS device.

Example 7. The MEMS device of embodiment 1, wherein the anti-adhesion layer comprises at least one of an organic material and a roughened surface of each of the handle substrate and the MEMS substrate.

Example 8. A method for manufacturing a micro electro mechanical system (MEMS) device,

Forming an anti-adhesion layer on at least one respective surface of the handle substrate and the MEMS substrate;

Patterning the anti-adhesion layer to define a patterned anti-adhesion layer that does not cover at least one predetermined location associated with bonding of the handle substrate to the MEMS substrate; And

And bonding the handle substrate to the MEMS substrate at the at least one predetermined location.

Example 9. The method of embodiment 8, wherein forming the anti-adhesion layer comprises depositing an organic material on at least one surface of the handle substrate and the MEMS substrate.

Example 10. The method of embodiment 9, wherein patterning the anti-adhesion layer comprises physically removing the organic material from the at least one predetermined location.

Example 11. The method of embodiment 9, wherein patterning the anti-adhesion layer comprises lubrication of the organic material at the at least one predetermined location.

Example 12. The method of embodiment 9, wherein patterning the anti-adhesion layer comprises a photolithographic process.

Example 13. The method of embodiment 9, wherein patterning the anti-adhesion layer comprises at least one of a physical etch and a chemical etch of the at least one predetermined location.

Example 14. The method of embodiment 8, wherein patterning the anti-adhesion layer comprises rubbing a surface of each of the handle substrate and the MEMS substrate associated with the at least one predetermined location.

Example 15. The method of embodiment 14, wherein patterning the anti-adhesion layer comprises plasma etching the surface of each of the handle substrate and the MEMS substrate associated with the at least one predetermined location.

Example 16. The method of embodiment 8 wherein bonding the handle substrate to the MEMS substrate at the at least one predetermined location comprises fusion bonding the handle substrate to the MEMS substrate at the at least one predetermined location. Way.

Example 17. The method of embodiment 8 further comprising forming a conductive layer on at least one of the handle substrate and the MEMS substrate prior to forming the anti-adhesion layer, wherein the conductive layer comprises one Or more of the adhesive surface.

Example 18. The method of embodiment 17, wherein forming the conductive layer further comprises patterning the conductive layer in at least one region associated with the at least one adhesion location, wherein the conductive layer is in contact with the metal layer.

Example 19. The method of embodiment 8 wherein the anti-adhesion layer remains on the at least one feature associated with the MEMS device after patterning.

Example 20. A method for manufacturing a micro electro mechanical system (MEMS) device,

Forming an organic material on at least one respective surface of a handle substrate and a MEMS substrate and defining an anti-adhesion layer on at least one respective surface of the handle substrate and the MEMS substrate;

Patterning the anti-adhesion layer to define a patterned anti-adhesion layer that removes the anti-adhesion layer at one or more predetermined locations associated with bonding of the handle substrate to the MEMS substrate, wherein the anti-adhesion layer is patterned after the patterning, Remaining on the associated one or more features;

And bonding the handle substrate to the MEMS substrate at the at least one predetermined location.

Claims (10)

In microelectromechanical systems (MEMS) devices,
A handle substrate defining a first bonding surface;
A MEMS substrate having a MEMS device and defining a second bonding surface, wherein the handle substrate is bonded to the MEMS substrate via a bonding interface with the first bonding surface facing the second bonding surface. ; And
An anti-stiction layer disposed between the first bonding surface and the second bonding surface without residing on the bonding interface,
/ RTI > 2. The MEMS device of claim 1, wherein the handle substrate comprises a handle feature associated with the MEMS device, wherein the anti-adhesion layer is arranged on at least one of a MEMS-facing surface of the handle feature and a sidewall MEMS device. 2. The MEMS device of claim 1, wherein the MEMS device comprises a MEMS feature, wherein the anti-adhesion layer is arranged on at least one of a handle-facing surface and one or more sidewalls of the MEMS feature. . The MEMS device according to claim 1, wherein the anti-adhesion layer is arranged on both the handle substrate and the MEMS substrate. 2. The MEMS device of claim 1, wherein the at least one predetermined location comprises at least one bonding location, and wherein the handle substrate and the MEMS substrate are fusion bonded to each other at the one or more bonding locations. The MEMS device of claim 1, wherein a conductive layer is also disposed between the anti-adhesion layer and each of the handle substrate and the MEMS substrate, and wherein the conductive layer generally releases electrical charge associated with each handle substrate and the MEMS substrate And the MEMS device. The MEMS device of claim 1, wherein the anti-adhesion layer comprises at least one of an organic material and a roughened surface of each of the handle substrate and the MEMS substrate. A method for manufacturing a micro electro mechanical system (MEMS) device,
Forming an anti-adhesion layer on at least one respective surface of the handle substrate and the MEMS substrate;
Patterning the anti-adhesion layer to define a patterned anti-adhesion layer that does not cover at least one predetermined location associated with bonding of the handle substrate to the MEMS substrate; And
And bonding the handle substrate to the MEMS substrate at the at least one predetermined location. 9. The method of claim 8, further comprising forming a conductive layer on at least one of the handle substrate and the MEMS substrate prior to forming the anti-adhesion layer, wherein the conductive layer is disposed between the handle substrate and the MEMS substrate Wherein the at least one adhesive is located at one or more adhesive locations. A method for manufacturing a micro electro mechanical system (MEMS) device,
Forming an organic material on at least one respective surface of a handle substrate and a MEMS substrate and defining an anti-adhesion layer on at least one respective surface of the handle substrate and the MEMS substrate;
Patterning the anti-adhesion layer to define a patterned anti-adhesion layer that removes the anti-adhesion layer at one or more predetermined locations associated with bonding of the handle substrate to the MEMS substrate, wherein the anti-adhesion layer is patterned after the patterning, Remaining on the associated one or more features;
And bonding the handle substrate to the MEMS substrate at the at least one predetermined location.

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